Electric switch with coil spring contact



Sept. 3, 1968 L. H. MQROSKEY 3,400,236

ELECTRIC SWITCH WITH COIL SPRING CONTACT Filed Sept. 26, 1966 2 Sheets-Sheet 1 ll n mvazaamanunw i I IIIIIII III/I111.

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leamra fl Mien? INVENT WHA NN 6 M MANIGAL BY 7 rm far A I/mn/ L. H- M ROSKEY ELECTRIC SWITCH WITH COIL SPRING CONTACT Sept. 3, 1968 2 Sheets-Sheet 2 Filed Sept. 26, 1966 INVENTO WHANN 4' M MANIGAL 11/0010 for 4,,11200/ United States Patent 3,400,236 ELECTRIC SWITCH WITH COIL SPRING CONTACT Leonard H. McRoskey, Los Angeles, Calif., assignor, by

direct and Inesne assignments, to Republic Tool & Manufacturing Corp., a corporation of California Continuation-impart of application Ser. No. 488,431, Sept. 20, 1965. This application Sept. 26, 1966, Ser. No. 582,103

Claims. (Cl. 200-153) ABSTRACT OF THE DISCLOSURE An electric switch, especially for controlling circuits in toy devices, having a pair of contacts in which one of the contacts has a freely deflectable portion normally spring urged into a closed position of engagement with a fixed contact which may comprise a terminal of an electrical device, and a camming barrier of nonconducting material selectively movable into and out of a position between and separating the contacts, movement of the barrier being operable on the deflectable portion and acting to move it with respect to the fixed contact.

This is a continuation-in-part of application Ser. No. 488,431, filed Sept. 20, 1965, now Patent No. 3,288,948.

The present invention relates generally to electric circuit controlling mechanisms, and is more particularly concerned with improvements in an electric switch which is especially suited for the control of motor and other electric circuits in connection with toy devices.

Heretofore, in the case of switch mechanisms of the type utilized for the control of motor energizing circuits and other circuits as embodied particularly in various toy devices, the trend has in the main been to construct the switches of small size and simple construction in order to reduce their cost. As a result of such efforts, the switches have become unreliable, due to failure of parts, failure to function properly as well as for other causes which have in general made the currently available switches undesirable.

With the foregoing in mind, the present invention has for one object a switch of improved construction requiring a minimum of parts and assembly operations, which is susceptible of a long operating life, which will be free of failures, and which may be quickly assembled and connected with the circuit conductors of a control circuit without the use of tools.

A further object is to provide in switches of the herein described character, unique contact members in the form of one or more coiled springs, advantage being taken of the spring coils to provide the mounting for the contact, connections for circuit conductors, and a contact portion which is of flexible character.

A still further object is to provide switch contacts embodying a coiled spring in which the coils operate to effect self cleaning of the contacts.

Another object is to provide in such switches, a contact embodying the use of a coiled spring which serves to provide through its construction and flexibility a frictional contact pressure.

It is also an object to utilize a contact having the structure of a coiled spring, in which the individual coils will serve as locking or dwell means for retaining an associated slide contact in its circuit closed position against inadvertent displacement.

Still another object of the invention is to provide unique switching means, wherein a connection contact of an associated device such as a battery, electric lamp and the like may be utilized as one of the contacts for the switching means.

3,400,236 Patented Sept. 3, 1968 Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.

Referring to the accompanying drawings, which are for illustrative purposes only:

FIG. 1 is an enlarged elevational view, partly in section, of an electric switch embodying the features of the present invention;

FIG. 2 is a fragmentary plan view of the same, showing the switch contacts in opened position;

FIG. 3 is a fragmentary plan view, showing the contacts in closed position;

FIG. 4 is a fragmentary detail view showing an alternate construction for the movable contact of the switch;

FIG. 5 is a fragmentary plan view of a modified form of the invention;

FIG. 6 is a transverse section of the same, taken substantially on line 6-6 of FIG. 5;

FIG. 7 is a fragmentary plan view of another modified form of the invention; and

FIG. 8 is a transverse section taken substantially on line 88 of FIG. 7.

Referring now more specifically to the drawings, for illustrative purposes, the switch of the present invention is disclosed in FIG. 1 as being incorporated in connection with a wall forming member 10 which may constitute a side wall, partition or the like of a compartment or container having a bottom closure wall 11. While the switch parts are shown as being thus associated, it is within the broad concepts of the present invention to utilize other forms of construction for the housing and mounting of the switch parts into cooperative relationship.

As shown in the disclosed embodiment, the wall 10 is provided with integrally formed spaced apart guide rails 12 and 13 which project from the adjacent surface of the wall 10 and provide confronting channels 14 and 15 which are utilized for removably supporting and positioning the cooperatively associated switching instrumentalities in a manner which will now be explained.

A movable switch body, as indicated by the numeral 16, is provided, this body comprising an elongate memher which is constructed of a suitable plastic or other suitable material preferably having insulating properties and of flat uniform thickness. One end of the member 17 is enlarged to form a head portion 18 of generally circular perimeter, and of a size to extend into the channels 14 and 15 on its opposite side edges. The member 17 is of less thickness than the width of the channels, and in order to center the member in the channels, the head portion may be provided with an overlying semicircular disc 19 on its opposite sides to serve as a spacer.

The opposite end of the member 17 is extended beyond the Wall member 10 and tapered to provide a handle portion 20 by means of which the member 17 may be rocked or swung about its head portion 18 for manipulating the switch contacts into and out of engagement.

A movable contact 21 is carried by the member 17, and comprises in the embodiment shown in FIG. 1 a tubular sleeve of conducting material such as copper, aluminum and the like which is supported upon a projecting portion or finger 22 that is integrally formed on the movable switch body. As best shown in FIG. 2 the sleeve is provided with opposite sides which converge to provide in effect a knife edge 23 to facilitate movement of the movable contact 21 into engagement with an operably associated contact as generally indicated at 24. In utilizing a contact sleeve structure as just described, a circuit conductor such as the conductor 25 may be connected to the contact by leading an end portion of the conductor from one side of the member 17 to the other through an opening 26 which will anchor the conductor and permit the insertion of an end of the conductor from which the insulation has been stripped, as indicated at 27 between the contact sleeve and the projecting portion 22.

The contact 24 is in the form of a relatively tightly coiled spring formed of electrically conducting spring wire. As thus constructed, the contact may be mounted upon one of the guide rails or other projection simply by spreading adjacent intermediate coil turns and pushing the coil spring over the edge of the projection or rail portion, in the manner shown in FIG. 1. As thus mounted, the adjacent coil turns frictionally grip the support and retain the contact in a mounted position with end portions extending on opposite sides thereof.

With a right-hand wound spring the inclination of the gripping coils act to support the spring with its axis at such an angle, with respect to the plane of movement of the movable contact, as to desirably assure proper closing of the contacts. The outermost end of the contact provides means by which a conductor 28 may have its stripped end 29 connected to the contact simply by inserting this stripped end between adjacent coil turns in the manner shown in FIG. 1.

The opposite end of the contact member is shown as being tapered as indicated at 30 by reducing the diameter of the coil turns in a direction towards the adjacent end of the contact member. By providing a tapered end, the movement of the contacts into closed position will be further facilitated.

Referring to FIG. 2, it will be observed that the tapered portion of the contact 24 is in the path of movement of the knife edge 23 of the movable contact, and that as the contacts are closed the knife edge will ride up on the tapered end 30 of the contact 24 and in so doing may deflect both the member 17 and the end portion of the spring as indicated in FIG. 3. Pressure frictional engagement is thus formed between the contacts so as to establish a good current flow connection. It will also be appreciated that the spring coils at this end of the contact will have an inherent cleaning effect due to their relative movement during opening and closing of the switch contaets. Moreover, there is a desirable tendency of the coils of the contact 24 to form a locking engagement with the movable contact which will tend to hold the movable contact in its closed position.

Referring to FIG. 4, there is shown an alternate arrangement for the movable contact which differs with that previously described in that instead of utilizing a sleeve for the contact 21, the contact as indicated at 21' in this case embodies a coiled spring which functions in the same manner as the previously explained contact. In this arrangement, it will be observed that the coiled springs as used in the moving contact and contact 24 will have their axes disposed at an angle, and the previously explained advantages for the contact 24, will also be present in the contact 21. Thus, the conductor 25 may have its bared end 27 anchored in the contact 21' by inserting it between the coil turns of the contact. Moreover, the contact 21 will also be deflected in the closed position of the contacts.

The modified versions of the invention as shown in FIGS. to 8 inclusive differ from the arrangements described above primarily by utilizing a switch contact arrangement wherein it is possible to utilize a connection contact of an associated device, such as a battery, electric lamp and the like as one of the contacts of the switching mechanism. This amounts to a material saving in cost, while at the same time permitting utilization of the unique features of the invention.

As shown more specifically in FIG. 5, this modification embodies a frame structure 31 which is adapted to receive and support an associated electrical device, namely, a battery 32 of the type utilized for flashlights and similar devices. This battery is of conventional construction and has a central electrode contact 33 at one end.

Adjacent the contact 33, the underlying frame structure is constructed with spaced walls 34 and 35 which define an internal cavity 36. The frame structure is so arranged that the wall 34 will extend just below the contact 33. This wall is provided with an integrally formed projection 37 which serves as a support for a resilient contact 38 which is similar to the previously described contact 24 in the form of a relatively tightly coiled spring of electrically conducting spring wire. This contact as mounted on the projection 37 has a free end 39 which is normally laterally deflected so that this end of the contact will be forcibly urged into engagement with the electrode contact 33 of the battery.

For controlling actuation of the switch which is thus formed by the contacts 33 and 38, there is provided an actuator which comprises a slide member 40 supported in the internal cavity 36 for rectilinear movement. This slide member carries an upper projection 41, as viewed in FIG. 6, which guidingly extends through an elongate slot 42 in the wall 34. The projection 41 has a bevelled edge 43 so that the projection will serve as a camming barrier which can be moved into and out of a position as shown in full lines in FIG. 5 between and separating the contacts 33 and 38. Upon movement of the projection 41 to the dotted line position, FIG. 5, the contact 38 will be forcefully urged into engagement with contact 33. The projection 41 is of non-conducting material and may be constructed of a plastic or insulation either separately or integrally with the slide member 40.

The slide member 40 also has a downwardly extending projection 44 which extends through a guide slot 45 in the wall 35. The projection 44 provides a digitally engageable handle for manually shifting the slide member during operation of the switch.

Referring now to FIG. 7, there is shown a modification which works on the same principles as that shown in FIG. 5, except that instead of the camming barrier being movable rectilinearly, it is movable in an arcuate path. More specifically, the arrangement shown in FIG. 7 is adapted to a combination which utilizes, for example, a light bulb device as generally indicated at 46 of conventional construction and having a conducting cylindrical base 47.

In this arrangement, the embodiment includes a frame structure 31' having an annular bottom wall 48, a surrounding side wall 49 at its periphery, this side wall at its upper edge being extended to provide an upwardly flared wall portion 49'. Centrally, the bottom wall is provided with an upstanding tubular sleeve 50 which serves as a receiving socket for the base contact 47, this sleeve at one side having a cut out opening or notch 51 therein which extends between notch forming edges 52 and 53. As thus arranged, the surface of the base contact 47 is exposed in the notch. Similarly, as described above, a coil contact 38 is in this case supported in the circular peripheral wall 49 with a free end portion 39 extending across the notch and being deflectingly resiliently urged into engagement with the surface of the cylindrical base contact 47 therein.

For controlling the switch contacts, which are thus formed by the base contact 47 and the contact 38', there is provided in this case an outer sleeve member 54 which is mounted in concentric surrounding relation to the sleeve 50. The outer sleeve member 54 is likewise provided with a notch 55 which extends between bevelled notch forming edges 56 and 57 which are shown as being bevelled so as to form camming edges. The notch 55 is substantially in registration with the notch 51. The sleeve 54 is rotatable by means of a radially extending handle 58.

With the handle 58 in the position shown in full lines, FIG. 7, the contact 38 will be in circuit engagement with the base contact 47. However, upon moving the handle 58 to the dotted line position, the notch edge 56 will be moved with camming action between the contacts 38 and 47 to form a separating barrier and hold the contacts in open position.

From the foregoing description and drawings, it will be clearly evident that the delineated objects of the invention will be accomplished.

Various modifications may suggest themselves to those skilled in the art without departing from the spirit of my invention, and, hence, I do not wish to be restricted to the specific form shown or uses mentioned, except to the extent indicated in the appended claims.

I claim:

1. An electric switch, comprising:

(a) a pair of cooperable associated contacts having engaged and disengaged positions, one of said contacts being fixed and one of said contacts being a supported member having a freely deflectable portion forcibly urged into engagement with the fixed contact in response to a pre-stressing deflection of said portion laterally away from its normal axis position; and

(b) manually movable means including a camming member for actuating said contacts to a disengaged position, said member having a path or movement passing between said contacts and in one direction of movement into engagement with said defiectable portion and acting to move said portion out of engagement with the fixed contact.

2. An electric switch according to claim 1, in which the supported member is an elongate coiled spring having coils in an end portion urged into engagement with the other contact.

3. An electric switch according to claim 1, wherein the manually movable means includes a camming member supported for movement along an arcuate path into and out of a position for separating the contacts.

4. Electric switching means comprising in combination:

(a) a battery mounted in a fixed position and having an electrode contact at one end;

(b) a coiled spring contact member fixedly supported and having a free laterally deflected end portion with coil turns thereof resiliently urged into electrical conducting contact engagement with said electrode contact; and

(c) a camming barrier of nonconducting material supported for movement into and out of a position between and separating said contacts, the barrier movement into said position acting to engage and move the coiled spring in a direction to disengage said coil turns from said electrode contact.

5. Electric switching means comprising in combination:

(a) a support including a tubular inner sleeve of insulating material having a wall opening on one side;

(b) an electrically energizable device having a cylindrical part coaxially supported in said sleeve and providing a connection contact member for the device;

(0) a coiled spring contact member fixedly supported and having a free laterally deflected end portion extending across said wall opening and being resiliently urged into electrical conducting engagement with said connection contact member; and

(d) concentric outer sleeve means rotatable on said inner sleeve, said outer sleeve means including an arcuate camming barrier of nonconducting material movable into and out of a position between and separating said contact members.

References Cited UNITED STATES PATENTS 2,215,319 9/1940 Brown 200153.14 XR FOREIGN PATENTS 135,864 12/1929 Switzerland.

ROBERT K. SCHAEFER, Primary Examiner.

H. BURKS, Assistant Examiner. 

